DOMIcondens F 24 D - F 28 D
33
EN
cod. 3541C751 - Rev. 00 - 10/2013
Water system characteristics
In the presence of water harder than 25° Fr (1°F = 10ppm CaCO
3
), use suitably treated
water in order to avoid possible scaling in the boiler.
Antifreeze system, antifreeze fluids, additives and inhibitors
When necessary, antifreeze fluids, additives and inhibitors can be used only if the man-
ufacturer of such fluids or additives guarantees that they are suitable and do not cause
damage to the exchanger or other components and/or materials of the boiler and system.
Do not use generic antifreeze fluids, additives or inhibitors that are not specific for use in
heating systems and compatible with the materials of the boiler and system.
3.4 Gas connection
B
Before making the connection, ensure that the unit is arranged for operation
with the type of fuel available.
The gas must be connected to the relevant connection (see fig. 8) in conformity with the
current standards, using a rigid metal pipe or a continuous surface flexible s/steel tube
and installing a gas cock between the system and boiler. Make sure all the gas connec-
tions are tight.
3.5 Electrical connections
Important
B
The unit must be connected to an efficient earthing system in conformity with
current safety regulations. Have the efficiency and suitability of the earthing
system checked by professionally qualified personnel; the Manufacturer de-
clines any liability for damage caused by failure to earth the system.
The boiler is prewired and provided with a "Y" type cable (without plug) for con-
nection to the electric line. The connections to the power supply must be per-
manent and equipped with a double-pole switch with contact opening distance
of at least 3 mm, installing fuses of max. 3A between the boiler and the line.
Make sure to respect the polarities (LINE: brown wire / NEUTRAL: blue wire /
EARTH: yellow/green wire) in connections to the electric line.
B
The unit's power cable must not be replaced by the user; if damaged, switch
the unit off and have the cable replaced by professionally qualified personnel.
If replacing the power cable, only use
"HAR H05 VV-F"
3x0.75 mm2 cable with
max. ext. diameter of 8 mm.
Room thermostat (optional)
B
IMPORTANT: THE ROOM THERMOSTAT MUST HAVE VOLTAGE-FREE
CONTACTS. CONNECTING 230 V TO THE ROOM THERMOSTAT TERMI-
NALS WILL PERMANENTLY DAMAGE THE ELECTRONIC BOARD.
When connecting time controls or a timer, do not take the power supply for
these devices from their breaking contacts Their power supply must be by
means of direct connection from the mains or with batteries, depending on the
kind of device.
Accessing the electrical terminal block
The electrical terminal block can be accessed after removing the casing. The layout of
the terminals for the various connections is also given in the wiring diagram in fig. 24.
fig. 9 - Accessing the terminal block
3.6 Fume ducts
Important
The unit is “type C” with sealed chamber and forced draught; the air inlet and fume outlet
must be connected to one of the following extraction/suction systems. Before installation,
check and carefully observe the above prescriptions. Also, comply with the provisions
concerning the positioning of wall and/or roof terminals and the minimum distances from
windows, walls, vents, etc.
Expansion
A
For fume exhaust pipes longer than 1 metre, during installation take in account
the natural expansion of the materials when the boiler is operating.
To prevent any deformation, leave an expansion space of approx. 2 ÷ 4 mm for
every metre of pipe.
Baffles
Boiler operation requires fitting the baffles supplied with the unit, according to that given
in the following tables.
Before inserting the fume exhaust pipe, check the presence of the right baffle (when it is
to be used) and that it is correctly positioned. The boilers are fitted standard with the
smallest diameter baffle. To replace the baffle (ref. 1 - fig. 10), proceed as indicated in
fig. 10.
fig. 10
Connection with coaxial pipes
fig. 11 - Examples of connection with coaxial pipes (
= Air /
= Fumes)
For coaxial connection, fit the unit with one of the following starting accessories. For the
wall hole dimensions, refer to the figure on the cover. Any horizontal sections of the fume
exhaust must be kept sloping slightly towards the outside, to prevent condensate from
flowing back towards the unit.
fig. 12 - Starting accessory for coaxial ducts
1
2 3 4
5 6
72
139
138
3
4
1
C
12
C
12
C
32
C
32
C
32
C
12
041001X0
041002X0
041006X0
Ø 102
Ø 61.5
Ø 127
Ø 80.5
120
120
90.5
68.5
Ø 100.5
Ø 61.6
